Several thousand nationalists are marching in Moscow to call for ethnic Russians to "take back" Russia.
RFE/RL correspondents say more that than 10,000 have been participating in the march.
The event's organizers claim that the turnout is around 25,000 people, although the city police department put this figure at 7,000.
According to RFE/RL's reporters, the start of the march was delayed because metal detectors could not cope with the flow of people.
The so-called "Russian March" has been held annually since 2005 when a National Unity Day was declared on November 4 to replace the communist holiday of November 7 celebrating the 1917 Bolshevik Revolution.
This year's march is taking place amid growing resentment
among some Russians over Muslim migrants from Russia's Caucasus and the money the government sends to the restive region.
Protesters chanted "Russia For Russians" and "Migrants today, occupiers tomorrow" as they marched in Moscow.
Protests with hundreds of people were reported to have been held in several other Russian cities as well.
with agency reports